The present invention relates to the field of controlled pharmaceutical delivery, particularly to corticosteroids.
Compounds classified as corticosteroids, such as triamcinolone, can effectively treat some forms of neovascularization such as corneal neovasularization. In general, corticosteroids have been unsuccessful in treating neovscularization of the posterior segment. In many patients, these compounds cause undesirable side effects. These adverse affects include elevations in intraocular pressure and the formation of, or acceleration of, the development of cataracts. Elevations in intraocular pressure are of particular concern in patients who are already suffering from elevated intraocular pressure, such as glaucoma patients. Moreover, a risk exists that the use of corticosteroids in patients with normal intraocular pressure will cause elevations in pressure that result in damage to ocular tissue. Since therapy with corticosteroids is frequently long term, i.e., several days or more, a potential exists for significant damage to ocular tissue as a result of prolonged elevations in intraocular pressure attributable to that therapy.
One approach to solving the foregoing problems has been to search for specific compounds which are effective in treating neovascularization without elevating intraocular pressure. Another approach has been to administer corticosteroids in conjunction with another drug to xe2x80x9cblockxe2x80x9d or reduce the IOP elevating effects of the corticosteroids or to treat IOP elevation separately with another drug. A further approach has been to intravitreally inject corticosteroids to treat ocular neovascularization.
There exists a need for an improved method for treating and/or preventing retinal diseases with corticosteroids.
An object of the present invention is to provide a method for treating and/or preventing ocular diseases which have neovascularization as a component with corticosteroids without the associated adverse side effects.
Additional objects, advantages and other features of the invention will be set forth in the description which follows and in part will become apparent to those having ordinary skill in the art upon examination of the following or may be learned from the practice of the invention. The objects and advantages of the invention may be realized and obtained as particularly pointed out in the appended claims.
According to the present invention, the foregoing and other objects are achieved in part by a method for administering a corticosteroid to a posterior segment of an eye, the method comprising the step of:
implanting a sustained release device to deliver the corticosteroid to the vitreous of the eye wherein aqueous corticosteroid concentration is less than vitreous corticosteroid concentration during release.
In accordance with the present invention, the foregoing and other advantages are also achieved in part by an implantable, sustained release device for administering a corticosteroid to a posterior segment of an eye, the device comprising:
a corticosteroid, wherein the device is configured to provide sustained release of the corticosteroid to the vitreous of the eye such that aqueous corticosteroid concentration remains less than vitreous corticosteroid concentration during the release.